* {
  padding: 0;
  margin: 0;
  box-sizing: border-box;
}

body {
  overflow: hidden;
  background: gray;
}

.container {
  position: relative;
}

.tools {
  position: absolute;
  top: 10px;
  padding: .5em;
  background: #ccc;
}

.tools>div {
  margin-bottom: .5em;
  width: 1.2em;
  height: 1.2em;
  border-radius: 50%;
}

.tools>div:hover {
  cursor: pointer;
  border: solid 1px blue;
}

.penBlack {
  background: black;
}

.penWhite {
  background: white;
}

.penRed {
  background: red;
}

.tools div:nth-child(4),
.tools div:nth-child(5),
.tools div:nth-child(6) {
  line-height: 1.1em;
}

.tools .penEraser {
  height: 2.6em;
  border-radius: 0;
  background: white;
}

.tools .bgcBlack,
.tools .bgcWhite {
  border-radius: 0;
}

.tools .bgcBlack {
  background: black;
}

.tools .bgcWhite {
  background: white;
}